Where does “tres” come from?

tres (Bikol Central) comes from Spanish tres, from Latin trēs, from Proto-Italic trēs, from Proto-Indo-European *tréyes.

Ancestry of “tres”, step by step

StepLanguageWordMeaning
1Spanishtresthree
2Latintrēsthree; 3
3Proto-Italictrēsthree
4Proto-Indo-European*tréyes—
Every word from Proto-Indo-European *tréyes →Every word from Proto-Italic trēs →Every word from Latin trēs →